An acid trap is a sharp angle where two traces, or a trace and a pad, meet at less than 90 degrees and form a narrow pocket. Etchant can linger in that corner and over-etch the copper, and residues can collect there, so fabricators and DFM tools flag it. Designers avoid them by joining traces at 90 degrees or more, or by adding fillets.
Heard on the job
DFM came back with twelve acid traps on the power routing, square off those junctions before we release.
Also heard as
- etch trap
Related terms
Sliver
Very narrow strip of copper or soldermask in the artwork that can peel loose during fabrication.
Etching
Chemical removal of unwanted copper from a board, leaving only the protected circuit pattern.
DFM
Design for manufacturability: checking and adjusting a design so it can be built reliably at sensible cost.